The invention relates to superconducting tape. More particularly, the invention relates to superconducting tape having reduced AC losses. Even more particularly, the invention relates to methods of making a superconducting tape having reduced AC losses.
High temperature superconducting tapes, particularly those based on a superconducting yttrium barium copper oxide (YBCO) coating or layer, are being incorporated into applications, such as power transmission, motors, generators, and transformers. In such devices, an alternating current (AC) is passed through the tape.
Although they possess excellent properties when carrying direct current, YBCO-based coated conductors tend to exhibit high losses when used in AC current applications, such as those mentioned above. One approach to reducing such losses has been to divide the tape geometry into strips using standard lithographic techniques. Using this method, narrow strips of the superconducting layer are etched away, leaving a series of parallel superconducting segments. Not only are such lithographic methods costly and time-consuming, but they also are not readily usable with kilometer lengths of superconducting tape that are envisioned in production.
Means of reducing AC losses that are currently available are not adaptable to processing long lengths of superconducting tape. Therefore, what is needed is a method of making superconducting tape having reduced AC losses, wherein the method is adaptable to continuous processing of long lengths of such tape. What is also needed is a superconducting tape that exhibits reduced AC losses.